USA – Floods in Hawaii After Torrential Rain From Hurricane Lane

Hurricane Lane unleashed torrential rainfall in parts of Hawaii from 22 August, 2018, causing flooding and landslides.

On Aug. 22 at 1:48 a.m. EDT (0548 UTC) the GPM core satellite passed over Hurricane Lane when it was a Category 5 hurricane in the Central Pacific Ocean. GPM found very heavy rain occurring in powerful storms located in Lane’s well defined eye wall. Moderate to heavy rainfall was also covering a large area extending outward from the eye. Credits: NASA/JAXA, Hal Pierce

Hurricane Lane weakened and was downgraded to a tropical storm as it moved towards Hawaii. However, the storm still brought huge amounts of rainfall.

NWS Honolulu said rains associated with former Hurricane Lane produced the third highest storm total rainfall from a tropical cyclone in the USA since 1950. Some areas of Big Island (Hawaii Island) recorded more than 50 inches (1,270 mm) of rain from 22 to 26 August.

Honolii Stream near Papaikou jumped from 3 feet (0.9 metres) to the minor flood stage mark of 15 feet (4.5 metres) in the space of 12 hours on 22 August. The stream peaked at 18.3 feet (5.57 m) on 23 August.

Levels of the Wailuku River at Piihonoua also jumped dramatically and reached 24.2 feet (7.37 metres), well above minor flood stage of 18 feet (5.48 m).

Emergency teams were called on to rescue around 50 people trapped in flood water since 23 August. According to Hawaii County Civil Defense, neighborhoods around Hilo were evacuated on 24 August.

Numerous roads have been blocked or closed in several locations on Big Island due to wind damage, land slips and flood debris. Power outages also affected some areas. Authorities will carry our full damage assessments over the coming days.

Rainfall from Hurricane Lane, Hawaii, August 2018. Image: NWS Honolulu

Further Warnings

Hurricane Lane passed dangerously close to the islands before weakening. Flood warnings remain in place across much of Hawaii as further rain is expected in the wake of Hurricane Lane.

NWS Honolulu said “Moisture left behind in Lane’s wake will continue to bring showers to the islands through Tuesday. Windward locations are expected to receive the bulk of the rain.”

Social Media

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Flood Summary

Last updated: August 30, 2018
Event
Hurricane Lane, Hawaii, USA, August 2018
Date
August 22, 2018
Type
Flash flood
Cause
Extreme rainfall
Hurricane Lane brought torrential rainfall to parts of Hawaii from 22 August, 2018, causing flooding and landslides on Hawaii Island (Big Island). Leftover moisture from Tropical Depression Lane brought further heavy rain, this time causing flooding on the island of Kauai from 27 August.

Locations

A - Hanalei
B - Hilo

Magnitude

Rainfall level
883.41 mm in 48 hours
Mount Waialeale - August 27 to August 29, 2018
Figures according to NWS Honolulu
Rainfall level
497.84 mm in 48 hours
North Wailua Ditch - August 27 to August 29, 2018
NWS Honolulu
Rainfall level
464.06 mm in 48 hours
Hanalei - August 27 to August 29, 2018
NWS Honolulu
Rainfall level
1308.86 mm in 96 hours
Mountain View - August 22 to August 26, 2018
Figures according to NWS Honolulu
Rainfall level
1247.14 mm in 96 hours
Waiakea Uka - August 22 to August 26, 2018
NWS Honolulu
Rainfall level
1205.99 mm in 96 hours
Piihonua - August 22 to August 26, 2018
NWS Honolulu
Rainfall level
1198.88 mm in 96 hours
Saddle Quarry - August 22 to August 26, 2018
NWS Honolulu
River level
5.57 metres
Honolii Stream near Papaikou - August 23 to August 23, 2018
Minor flood stage is 15 feet (4.5 metres)
River level
7.37 metres
Wailuku River at Piihonoua - August 22 to August 23, 2018
Minor flood stage is 18 feet (5.48 m).
River level
7.13 metres
Halaulani Stream near Kilauea - August 28 to August 28, 2018
Major flood stage is 2.97m

Damages

Evacuated
50 people
Hilo - August 23 to August 24, 2018
Evacuated
50 people
Hanalei - August 28 to August 30, 2018
Estimated figure